Poison-based avoidance conditioning, the learned avoidance of novel substances when their ingestion is followed by gastrointestinal malaise, has obvious survival value, and genetic selection may have been contributory. If so, the avoidance conditioning paradigm would be less susceptible to drug-state dependency. This would be tested in rats, using three drugs at dosages known to have state dependent effects on other kinds of avoidance conditioning and learning. The drugs are: delta 9-THC, ethanol and pentobarbital.